Biometric security systems measure a user's physiological characteristics to confirm the identity of a user. Biometric sensors that may be used include facial recognition systems, fingerprint identification systems, retinal scanning systems, and voiceprint identification systems. Because the biometric sensors actually measure a physical characteristic, they may be deemed more secure in that they require the user to actually possess the physical characteristic, rather than merely to know something, as is the case with passwords. Also, a security system that uses physiological characteristics of a user may be considered by some to be a more difficult system to defeat.